I overheard someone saying something like 'with tree, pole and pen, so will you know Cornish men' (??). What were they on about? I'm from Cornwall and I've never heard that rhyme before.
Trees, poles and pens are all somewhat phallic. Cornishmen are known for their virility, especially with their own family members.
This stereotype goes back several hundred years; in fact Uther Pendragon is largely responsible for popularising the myth of the virile Cornishman.
The actual rhyme goes something like, 'By tre, pol and pen, so shall ye know Cornishmen', and it refers to the common usage of the suffixes tre (settlement), pol (pool or lake) and pen (hill) in Cornish personal and place names. Remember Poldark?
It's not tree, pole and pen it's 'tre, pol and pen' - three common prefixes in Cornish names and place names.
For example, Pen means headland and Dynas is Castle so if you translate Pendennis Castle, it says Headland Castle Castle.
Tester's unpleasant ramblings will offend 40,000 Cornishmen. He'd better watch it.